Mozilla developers post a screenshot of what Firefox 3.0's unified bookmarks, history and downloads manager—named Places—may look like. Being just a mockup, the final product probably won't turn out exactly like this, but it's a neat preview of features in the works. Highlights include tags, search and page previews right inside the Places Organizer. After the jump get the full screenshot and a glimpse into the minds of the makers of our favorite browser. (Warning: huge image ahead.)